<template>
  <div class="article-container">
    <!-- 导航栏 -->
    <van-nav-bar
      class="page-nav-bar"
      left-arrow
      title="黑马头条"
    ></van-nav-bar>
    <!-- /导航栏 -->

    <div class="main-wrap">
      <!-- 加载中 -->
      <div v-if="isLoading" class="loading-wrap">
        <van-loading
          color="#3296fa"
          vertical
        >加载中</van-loading>
      </div>
      <!-- /加载中 -->

      <!-- 加载完成-文章详情 -->
      <div v-else-if="articles.title" class="article-detail">
        <!-- 文章标题 -->
        <h1 class="article-title">{{ articles.title }}</h1>
        <!-- /文章标题 -->

        <!-- 用户信息 -->
        <van-cell class="user-info" center :border="false">
          <van-image
            class="avatar"
            slot="icon"
            round
            fit="cover"
            :src="articles.aut_photo"
          />
          <div slot="title" class="user-name">{{ articles.aut_name }}</div>
          <div slot="label" class="publish-date">{{ articles.pubdate | formatDate }}</div>
          <!-- v-model -->
          <!-- v-model: 可以在表单上使用 -->
          <!-- v-model: 还可以在组件上使用 -->
          <!-- 什么时候用: 既要传数据,子组件还要改数据 -->
          <!-- 怎么用: v-model="要传递的数据" -->
          <!-- <UserFollowed @updateIsFollowed="articles.is_followed = $event" :autId="articles.aut_id" :isFollowed="articles.is_followed" /> -->
          <UserFollowed
          :autId="articles.aut_id"
          v-model="articles.is_followed"
          />
          <!-- v-mode是如何解析的(默认解析) -->
          <!--
            解析两个
            1个属性:  :value="articles.is_followed" 给子组件传值传了 value
            1个事件: @input="articles.is_followed = $event"
          -->
          <!-- <UserFollowed
          :autId="articles.aut_id"
          :value="articles.is_followed"
          @input="articles.is_followed = $event"
          /> -->
        </van-cell>
        <!-- /用户信息 -->

        <!-- 文章内容 -->
        <div class="article-content" v-html="articles.content" ref="content"></div>
        <van-divider>正文结束</van-divider>

        <!-- 文章评论 -->
        <ArticleComment
        @updateTotal="totalCount = $event"
        @click-reply="clickReply"
        :list="list"
        :source="articles.art_id"/>
      </div>
      <!-- /加载完成-文章详情 -->

      <!-- 加载失败：404 -->
      <div v-else-if="is404" class="error-wrap">
        <van-icon name="failure" />
        <p class="text">该资源不存在或已删除！</p>
      </div>
      <!-- /加载失败：404 -->

      <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
      <div v-else class="error-wrap">
        <van-icon name="failure" />
        <p class="text">内容加载失败！</p>
        <van-button @click="loadArticleInfo" class="retry-btn">点击重试</van-button>
      </div>
      <!-- /加载失败：其它未知错误（例如网络原因或服务端异常） -->
    </div>

    <!-- 底部区域 -->
    <div v-if="articles.title" class="article-bottom">
      <van-button
        class="comment-btn"
        type="default"
        round
        size="small"
        @click="isShowCommentPopup = true"
      >写评论</van-button>
      <van-icon
        name="comment-o"
        :badge="totalCount"
        color="#777"
      />
      <ArticleCollected
      :articleId="articles.art_id"
      v-model="articles.is_collected" />
      <!--
        1. :value="articles.is_collected"
        2. @input="articles.is_collected = $event"

        当子组件配置了model 按照model进行解析
       1. :collected="articles.is_collected"
      -->
      <van-icon
        color="#777"
        name="good-job-o"
      />
      <van-icon name="share" color="#777777"></van-icon>
    </div>
    <!-- /底部区域 -->

    <!-- 评论弹层 -->
    <van-popup v-model="isShowCommentPopup" position="bottom">
      <!-- 对文章进行评论 -->
      <ArticlePost @onPostSuccess="onPostSuccess" :target="articleId"/>
    </van-popup>

    <!-- 回复评论弹层 -->
    <van-popup
    v-model="isShowReplyCommentPopup"
    style="height: 100%"
    position="bottom">
      <ReplyPost
      @close-popup="isShowReplyCommentPopup = false"
      :comment="comment"
      v-if="isShowReplyCommentPopup"
      />
    </van-popup>

    <!-- 对评论进行评论 -->
    <!-- <ArticlePost :target="评论id" :artId="文章id"/> -->
  </div>
</template>

<script>
import { getArticleInfo } from '@/api/article.js'
import { ImagePreview } from 'vant'
import UserFollowed from '@/components/user-followed.vue'
import ArticleCollected from './components/article-collected.vue'
import ArticleComment from './components/article-comment.vue'
import ArticlePost from './components/article-post.vue'
import ReplyPost from './components/reply-post.vue'
export default {
  name: 'articles',
  data () {
    return {
      articles: {}, // 文章详情
      isLoading: false,
      is404: false,
      totalCount: 0,
      isShowCommentPopup: false,
      isShowReplyCommentPopup: false,
      list: [], // 存评论列表数据
      comment: {}
    }
  },

  components: {
    UserFollowed,
    ArticleCollected,
    ArticleComment,
    ArticlePost,
    ReplyPost
  },

  // 还可以接收路由的params的参数
  props: {
    articleId: {
      type: String
    }
  },

  created () {
    this.loadArticleInfo()
  },

  mounted () {
  },

  methods: {
    // 加载文章详情数据
    async loadArticleInfo () {
      this.isLoading = true
      try {
        const res = await getArticleInfo(this.articleId)
        this.articles = res.data.data
        this.isLoading = false // vue: 数据驱动 组件系统
        // 数据驱动是异步的 数据变是同步的 视图变 是异步的
        this.$nextTick(() => {
          this.previewImg()
        })
      } catch (err) {
        // 判断是否404的错误
        if (err.response && err.response.status === 404) {
          this.is404 = true
        }
        this.$toast('获取失败')
        this.isLoading = false // vue: 数据驱动 组件系统
        // 数据驱动是异步的 数据变是同步的 视图变 是异步的
      }
    },
    // 图片预览
    previewImg () {
      const imgs = this.$refs.content.querySelectorAll('img')
      const images = []
      imgs.forEach((item, index) => {
        images.push(item.src)
        item.onclick = function () {
          ImagePreview({
            images,
            startPosition: index
          })
        }
      })
    },
    // 监听子组件发布评论成功
    onPostSuccess (e) {
      // 给评论列表追加数据
      this.list.unshift(e)
      // 关闭弹层
      this.isShowCommentPopup = false
    },
    // 孙子组件点击回复
    clickReply (e) {
      // 显示弹层
      this.isShowReplyCommentPopup = true
      // 保存评论项数据
      this.comment = e
    }
  }
}
</script>

<style scoped lang="less">
.article-container {
  .main-wrap {
    position: fixed;
    left: 0;
    right: 0;
    top: 92px;
    bottom: 88px;
    overflow-y: scroll;
    background-color: #fff;
  }
  .article-detail {
    .article-title {
      font-size: 40px;
      padding: 50px 32px;
      margin: 0;
      color: #3a3a3a;
    }

    .user-info {
      padding: 0 32px;
      .avatar {
        width: 70px;
        height: 70px;
        margin-right: 17px;
      }
      .van-cell__label {
        margin-top: 0;
      }
      .user-name {
        font-size: 24px;
        color: #3a3a3a;
      }
      .publish-date {
        font-size: 23px;
        color: #b7b7b7;
      }
      .follow-btn {
        width: 170px;
        height: 58px;
      }
    }

    .article-content {
      padding: 55px 32px;
      /deep/ p {
        text-align: justify;
      }
    }
  }

  .loading-wrap {
    padding: 200px 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #fff;
  }

  .error-wrap {
    padding: 200px 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #fff;
    .van-icon {
      font-size: 122px;
      color: #b4b4b4;
    }
    .text {
      font-size: 30px;
      color: #666666;
      margin: 33px 0 46px;
    }
    .retry-btn {
      width: 280px;
      height: 70px;
      line-height: 70px;
      border: 1px solid #c3c3c3;
      font-size: 30px;
      color: #666666;
    }
  }

  .article-bottom {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    box-sizing: border-box;
    height: 88px;
    border-top: 1px solid #d8d8d8;
    background-color: #fff;
    .comment-btn {
      width: 282px;
      height: 46px;
      border: 2px solid #eeeeee;
      font-size: 30px;
      line-height: 46px;
      color: #a7a7a7;
    }
    .van-icon {
      font-size: 40px;
      .van-info {
        font-size: 16px;
        background-color: #e22829;
      }
    }
  }
}
</style>
